Place the potatoes into a pot and add salt. Pour water until potatoes are covered and bring to a boil. Simmer covered over medium-high heat until done - a fork can easily be poked through them.

Drain water. Peel the potatoes and mash them with a potato masher.

Melt the butter in a pot over medium heat. Add the mashed potatoes, milk, cream, salt and pepper; stir well.

Cook to desired thickness, stirring occasionally. Taste and adjust seasonings.